HIF介导的DEPTOR通过PDCD4c-Jun(AP-1)信号通路参与肝癌HepG2细胞侵袭和血管生成研究

HIF-mediated DEPTOR participates in the invasion and angiogenesis of liver cancer HepG2 cells through the PDCD4c-Jun(AP-1)signaling pathway

目的探讨缺氧诱导因子(HIF)介导的包括DEP结构域含有雷帕霉素靶蛋白相互作用蛋白(DEPTOR)通过程序性细胞死亡4(PDCD4)/c-Jun(AP-1)信号通路参与肝癌HepG2细胞侵袭和血管生成的过程。方法对数生长期的HepG2细胞侵分为3组-空白组、对照组与HIF组,对照组与HIF组分别转染HIF反义RNA-2对照与HIF反义RNA-2各1μg,空白组以等剂量的磷酸盐缓冲液代替。细胞转染后24 h与36 h,采用四甲基偶氮唑盐微量酶反应比色法(MTT法)实验检测细胞增殖,Transwell小室检测细胞侵袭,流式细胞仪检测细胞凋亡,免疫印迹法(Western blot)检测蛋白表达。结果细胞转染后24 h与36 h,HIF组的细胞增殖指数、侵袭指数均显著低于空白组与对照组,差异有统计学意义(P<0.05),细胞凋亡指数均显著高于空白组与对照组,差异有统计学意义(P<0.05),而空白组与对照组比较,差异无统计学意义(P>0.05)。细胞转染后24 h与36 h,HIF组的DEPTOR蛋白相对表达水平显著低于空白组与对照组,PDCD4与c-Jun(AP-1)蛋白水平显著高于空白组与对照组,差异有统计学意义(P<0.05),空白组与对照组比较,差异无统计学意义(P>0.05)。结论抑制HIF的表达能促进肝癌细胞凋亡,抑制细胞增殖与侵袭,能够介导DEPTOR蛋白的表达,从而促进PDCD4/c-Jun(AP-1)通路的激活与抑制血管生成。

Objective To investigate the involvement of hypoxia-inducible factor(HIF)-mediated DEPTOR participates in the invasion and angiogenesis of liver cancer HepG2 cells through the programmed cell death 4(PDCD4)/c-Jun(AP-1)signaling pathway.Methods HepG2 cells in the logarithmic growth phase were divided into three groups-blank group,control group and HIF group.The control group and HIF group were transfected with HIF antisense RNA-2 control and HIF antisense RNA-2 respectively of 1μg in each group,the blank group were transfected with the same dose of phosphate buffer.At 24 h and 36 h after cell transfection,MTT assay were used to detect cell proliferation,Transwell chamber to detect cell invasion,flow cytometry were to detect cell apoptosis,and Western blot to detect protein expression.Results At 24 h and 36 h after cell transfection,the cell proliferation index and invasion index of the HIF group were lower than the blank group and the control group,the difference was statistically significant(P<0.05),and the apoptosis index were higher than the blank group and the control group,the differences were statistically significant(P<0.05),and there were no significant difference compared between the group and the control group(P>0.05).At 24 h and 36 h after cell transfection,The relative expression level of DEPTOR protein in the HIF group were lower than that of the blank group and the control group,the differences were statistically significant(P<0.05),and the protein levels of PDCD4 and c-Jun(AP-1)were higher than the blank group and the control group,the differences were statistically significant(P<0.05),and there were no significant difference compared between the group and the control group(P>0.05).Conclusion Inhibiting the expression of HIF can promote liver cancer cell apoptosis,inhibit cell proliferation and invasion,and mediate the expression of DEPTOR protein,thereby promote the activation of PDCD4/c-Jun(AP-1)pathway and inhibit angiogenesis.